summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu
diff options
context:
space:
mode:
authorIngo Molnar <mingo@kernel.org>2017-08-26 09:19:13 +0200
committerIngo Molnar <mingo@kernel.org>2017-08-26 09:19:13 +0200
commit413d63d71b222108d19703f3fd5cf9108652a730 (patch)
tree4680de6aebb6430dc5f3d9327f86d65149e6b5ae /arch/x86/kernel/cpu
parentd6c8103b0265d8db30e20e948a4f06382bbdaea7 (diff)
parent90a6cd503982bfd33ce8c70eb49bd2dd33bc6325 (diff)
Merge branch 'linus' into x86/mm to pick up fixes and to fix conflicts
Conflicts: arch/x86/kernel/head64.c arch/x86/mm/mmap.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/cpu')
-rw-r--r--arch/x86/kernel/cpu/amd.c1
-rw-r--r--arch/x86/kernel/cpu/aperfmperf.c43
-rw-r--r--arch/x86/kernel/cpu/mcheck/therm_throt.c2
-rw-r--r--arch/x86/kernel/cpu/microcode/core.c4
-rw-r--r--arch/x86/kernel/cpu/mtrr/main.c18
5 files changed, 48 insertions, 20 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index f22fd4ea8858..110ca5d2bb87 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -134,6 +134,7 @@ static void init_amd_k6(struct cpuinfo_x86 *c)
n = K6_BUG_LOOP;
f_vide = vide;
+ OPTIMIZER_HIDE_VAR(f_vide);
d = rdtsc();
while (n--)
f_vide();
diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c
index d869c8671e36..0ee83321a313 100644
--- a/arch/x86/kernel/cpu/aperfmperf.c
+++ b/arch/x86/kernel/cpu/aperfmperf.c
@@ -8,20 +8,25 @@
* This file is licensed under GPLv2.
*/
-#include <linux/jiffies.h>
+#include <linux/delay.h>
+#include <linux/ktime.h>
#include <linux/math64.h>
#include <linux/percpu.h>
#include <linux/smp.h>
struct aperfmperf_sample {
unsigned int khz;
- unsigned long jiffies;
+ ktime_t time;
u64 aperf;
u64 mperf;
};
static DEFINE_PER_CPU(struct aperfmperf_sample, samples);
+#define APERFMPERF_CACHE_THRESHOLD_MS 10
+#define APERFMPERF_REFRESH_DELAY_MS 20
+#define APERFMPERF_STALE_THRESHOLD_MS 1000
+
/*
* aperfmperf_snapshot_khz()
* On the current CPU, snapshot APERF, MPERF, and jiffies
@@ -33,13 +38,18 @@ static void aperfmperf_snapshot_khz(void *dummy)
u64 aperf, aperf_delta;
u64 mperf, mperf_delta;
struct aperfmperf_sample *s = this_cpu_ptr(&samples);
+ ktime_t now = ktime_get();
+ s64 time_delta = ktime_ms_delta(now, s->time);
+ unsigned long flags;
- /* Don't bother re-computing within 10 ms */
- if (time_before(jiffies, s->jiffies + HZ/100))
+ /* Don't bother re-computing within the cache threshold time. */
+ if (time_delta < APERFMPERF_CACHE_THRESHOLD_MS)
return;
+ local_irq_save(flags);
rdmsrl(MSR_IA32_APERF, aperf);
rdmsrl(MSR_IA32_MPERF, mperf);
+ local_irq_restore(flags);
aperf_delta = aperf - s->aperf;
mperf_delta = mperf - s->mperf;
@@ -51,22 +61,21 @@ static void aperfmperf_snapshot_khz(void *dummy)
if (mperf_delta == 0)
return;
- /*
- * if (cpu_khz * aperf_delta) fits into ULLONG_MAX, then
- * khz = (cpu_khz * aperf_delta) / mperf_delta
- */
- if (div64_u64(ULLONG_MAX, cpu_khz) > aperf_delta)
- s->khz = div64_u64((cpu_khz * aperf_delta), mperf_delta);
- else /* khz = aperf_delta / (mperf_delta / cpu_khz) */
- s->khz = div64_u64(aperf_delta,
- div64_u64(mperf_delta, cpu_khz));
- s->jiffies = jiffies;
+ s->time = now;
s->aperf = aperf;
s->mperf = mperf;
+
+ /* If the previous iteration was too long ago, discard it. */
+ if (time_delta > APERFMPERF_STALE_THRESHOLD_MS)
+ s->khz = 0;
+ else
+ s->khz = div64_u64((cpu_khz * aperf_delta), mperf_delta);
}
unsigned int arch_freq_get_on_cpu(int cpu)
{
+ unsigned int khz;
+
if (!cpu_khz)
return 0;
@@ -74,6 +83,12 @@ unsigned int arch_freq_get_on_cpu(int cpu)
return 0;
smp_call_function_single(cpu, aperfmperf_snapshot_khz, NULL, 1);
+ khz = per_cpu(samples.khz, cpu);
+ if (khz)
+ return khz;
+
+ msleep(APERFMPERF_REFRESH_DELAY_MS);
+ smp_call_function_single(cpu, aperfmperf_snapshot_khz, NULL, 1);
return per_cpu(samples.khz, cpu);
}
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index d7cc190ae457..f7370abd33c6 100644
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -122,7 +122,7 @@ static struct attribute *thermal_throttle_attrs[] = {
NULL
};
-static struct attribute_group thermal_attr_group = {
+static const struct attribute_group thermal_attr_group = {
.attrs = thermal_throttle_attrs,
.name = "thermal_throttle"
};
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 9cb98ee103db..86e8f0b2537b 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -561,7 +561,7 @@ static struct attribute *mc_default_attrs[] = {
NULL
};
-static struct attribute_group mc_attr_group = {
+static const struct attribute_group mc_attr_group = {
.attrs = mc_default_attrs,
.name = "microcode",
};
@@ -707,7 +707,7 @@ static struct attribute *cpu_root_microcode_attrs[] = {
NULL
};
-static struct attribute_group cpu_root_microcode_group = {
+static const struct attribute_group cpu_root_microcode_group = {
.name = "microcode",
.attrs = cpu_root_microcode_attrs,
};
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index c5bb63be4ba1..40d5a8a75212 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -237,6 +237,18 @@ set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type typ
stop_machine(mtrr_rendezvous_handler, &data, cpu_online_mask);
}
+static void set_mtrr_cpuslocked(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ struct set_mtrr_data data = { .smp_reg = reg,
+ .smp_base = base,
+ .smp_size = size,
+ .smp_type = type
+ };
+
+ stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask);
+}
+
static void set_mtrr_from_inactive_cpu(unsigned int reg, unsigned long base,
unsigned long size, mtrr_type type)
{
@@ -370,7 +382,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
/* Search for an empty MTRR */
i = mtrr_if->get_free_region(base, size, replace);
if (i >= 0) {
- set_mtrr(i, base, size, type);
+ set_mtrr_cpuslocked(i, base, size, type);
if (likely(replace < 0)) {
mtrr_usage_table[i] = 1;
} else {
@@ -378,7 +390,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
if (increment)
mtrr_usage_table[i]++;
if (unlikely(replace != i)) {
- set_mtrr(replace, 0, 0, 0);
+ set_mtrr_cpuslocked(replace, 0, 0, 0);
mtrr_usage_table[replace] = 0;
}
}
@@ -506,7 +518,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
goto out;
}
if (--mtrr_usage_table[reg] < 1)
- set_mtrr(reg, 0, 0, 0);
+ set_mtrr_cpuslocked(reg, 0, 0, 0);
error = reg;
out:
mutex_unlock(&mtrr_mutex);